MN10300: fix debug polling in ttySM driver

The debug polling interface for the SoC serial ports did not work in the case where the serial ports were not also used as a console. In that case, the uart driver startup function will not be called so tx and rx would not be enabled in the hardware control register. Also, vdma interrupts would not be enabled which the poll_get_char function relied on. This patch makes sure that the rx and tx enables are set as a consequence of the uart set_termios call which is the only initialization done for the debug polling interface. Also, the poll_get_char now handles the case where vdma interrupts are not enabled. Signed-off-by: Mark Salter <[email protected]> Signed-off-by: David Howells <[email protected]>
mrcsosa · Dec 12, 2012 · 0369c36 · 0369c36
1 parent 97a70b1
commit 0369c36
Showing 1 changed file with 23 additions and 12 deletions.
diff --git a/arch/mn10300/kernel/mn10300-serial.c b/arch/mn10300/kernel/mn10300-serial.c
@@ -1374,7 +1374,8 @@ static void mn10300_serial_change_speed(struct mn10300_serial_port *port,
 	if ((new->c_cflag & CREAD) == 0)
 		port->uart.ignore_status_mask |= (1 << TTY_NORMAL);
 
-	scxctr |= *port->_control & (SC01CTR_TXE | SC01CTR_RXE | SC01CTR_BKE);
+	scxctr |= SC01CTR_TXE | SC01CTR_RXE;
+	scxctr |= *port->_control & SC01CTR_BKE;
 	*port->_control = scxctr;
 
 	spin_unlock_irqrestore(&port->uart.lock, flags);
@@ -1720,19 +1721,29 @@ static int mn10300_serial_poll_get_char(struct uart_port *_port)
 
 	_enter("%s", port->name);
 
-	do {
-		/* pull chars out of the hat */
-		ix = ACCESS_ONCE(port->rx_outp);
-		if (CIRC_CNT(port->rx_inp, ix, MNSC_BUFFER_SIZE) == 0)
-			return NO_POLL_CHAR;
+	if (mn10300_serial_int_tbl[port->rx_irq].port != NULL) {
+		do {
+			/* pull chars out of the hat */
+			ix = ACCESS_ONCE(port->rx_outp);
+			if (CIRC_CNT(port->rx_inp, ix, MNSC_BUFFER_SIZE) == 0)
+				return NO_POLL_CHAR;
 
-		smp_read_barrier_depends();
-		ch = port->rx_buffer[ix++];
-		st = port->rx_buffer[ix++];
-		smp_mb();
-		port->rx_outp = ix & (MNSC_BUFFER_SIZE - 1);
+			smp_read_barrier_depends();
+			ch = port->rx_buffer[ix++];
+			st = port->rx_buffer[ix++];
+			smp_mb();
+			port->rx_outp = ix & (MNSC_BUFFER_SIZE - 1);
 
-	} while (st & (SC01STR_FEF | SC01STR_PEF | SC01STR_OEF));
+		} while (st & (SC01STR_FEF | SC01STR_PEF | SC01STR_OEF));
+	} else {
+		do {
+			st = *port->_status;
+			if (st & (SC01STR_FEF | SC01STR_PEF | SC01STR_OEF))
+				continue;
+		} while (!(st & SC01STR_RBF));
+
+		ch = *port->_rxb;
+	}
 
 	return ch;
 }